UCSF is currently one of the ten original sites in the Biliary Atresia Research Consortium (BARC) and the Cholestatic Liver Consortium (CLiC) which is being continued, expanded and merged to form the Childhood Liver Disease Research and Education Network (ChiLDREN). The specific objectives of the newly formed ChiLDREN could include but are not limited to: 1) Completion of the steroid safety and efficacy clinical trial in biliary atresia. 2) Continuation of the BARC and CLiC prospective longitudinal studies of children to continue to provide data and biospecimens for ancillary studies aimed at discovering new diagnostics, etiologic and treatment options for children both pre and post liver transplantation. 3) Continuation of the prospective longitudinal study of cystic fibrosis liver disease (CFLD) aimed at identifying predictors of development of liver disease in children with CF as well as predictors of outcome in children with CFLD. 4) Identification and validation of non-invasive markers of liver disease in CF patients including but not limited to new imaging modalities. 5) Phase l/ll study of new agents to treat cholestasis in children. 6) Study of modifier genes in Alagille Syndrome and Alpha-1-antrypsin disease. 7) Expansion to include other diseases of cholestasis in children with industry and patient advocacy group support. 8) Continue to provide training opportunities for investigators in pediatric liver disease. 9) Continue to provide support for small pilot and demonstration projects within the Network.10) Continue to provide education about pediatric liver diseases to the scientific and lay communities through publications and the website. In addition, at UCSF we specifically plan to continue to investigate the role of HLA in biliary atresia in collaboration with Dr. Cara Mack at the University of Colarado. Further, in order to determine if rotavirus plays an etiologic role in biliary atresia, we plan to compare data from the former BARC database and new ChiLDREN database with CDC data for rotavirus activity in the United States. Dr. Bull plans to develop fast and reliable screening methods for diagnosis of PFIC. Relevance: Combining BARC and CLiC will enhance the capacity for unhindered flow of clinical information, allow for greater efficiency, permit standardization of process, data, and specimen collection methodology, allow the network to take advantage of available resources offered by lay organizations to expand the number of diseases studied, and include follow-up of children after transplant. Our specific studies at UCSF aim to aid in diagnosis and treatment of biliary atresia and PFIC.